Arm chair



FIG. 1 is a front perspective view of an arm chair showing my design;

FIG. 2 is a front elevational view;

FIG. 3 is a top plan view;

FIG. 4 is a rear elevational view;

FIG. 5 is a side elevational view; and

FIG. 6 is a bottom plan view thereof. 

The ornamental design for an arm chair, as shown. 